<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script type="text/javascript">
			var b=0;
			var c=0;
			var a="dfjd5555ffdfeww555wf";
			  for(var i=0;i<a.length;i++){
			   if(isNaN(a[i])==true){
			    c+=1;
			    }else{
			      b+=1;
			    }
			}
			
			document.write("字母个数:"+c+"<br />"  +"数字个数:"+b +"<br />");
			
			      var a=[['小红','女','21','大一'],['小黄','男','23','大二'],['小蓝','男','23','大三'],['大红','女','25','大一'],['中红','女','30','大一']];
			      for(i=0;i<a.length;i++){
			        if(a[i][3]=="大一"&&a[i][1]=="女"){
			          document.write(a[i][0]);
			          }
			      }
			
		</script>
	</body>
</html>
